基于L_1自适应方法的四旋翼飞行器纵向控制

Quadrotor Longitudinal Controller Based on L_1 Adaptive Control Method

针对四旋翼飞行器姿态控制系统欠驱动、强耦合、强振动的特性以及非零初始误差的客观存在,采用了一种新型的L1自适应算法,将模型的非线性因素和耦合项视作时变参数和干扰,设计了L1自适应控制器,突破了传统自适应控制固有的时变参数频率限制,有效抑制了飞行器机械振动所引起的高频干扰;同时,在飞行器存在非零初态跟踪误差情况下,避免了瞬态误差的出现,确保输入力矩在可控范围内一致有界。最后,仿真结果验证了算法的鲁棒性。

Focused on the characteristics of under-actuation,high-coupling,high-chattering and non-zero initial error of the quadrotor attitude control system,a longitudinal adaptive controller was designed by a novel L1adaptive control method in which the nonlinearity and coupling were regarded as time-varying vectors or disturbances.It breaks through the frequency limit of time-varying parameters of traditional adaptive control method,and the problem of high frequency disturbances caused by quadrotor oscillation was restrained effectively.The controller could avoid transient deviation and ensure the input moment being uniformly bounded in the control range under the condition of non-zero trajectory initialization error.The robustness of the method was proved by simulation.